I recently purchased a 2004 komfort 5th wheel trailer. the lights only work when I'm connected to 110. When i disconnect from 110, the lights won't work off the battery. Any ideas?
Look in compartment where battery is.....follow positive cable to the next item in line....a switch. It should be in ON position.
No switch.......then check the battery voltage. If voltage is low then recharge/get it load tested/get a new battery. THEN you need to check converter output....it should keep battery charged.
Hopefully you find a switch OFF and your battery is OK